1. Field of the Invention
The invention relates to safety belt retractors; and, more particularly, to emergency sensing retractors having improved pawl locking means.
2. Description of the Prior Art
Safety belt retractors which utilize energy derived from a rotating shaft for moving a pawl into engagement with a ratchet wheel mounted on a shaft are known in the prior art, such as the inertia reel mechanism described and claimed in U.S. Pat. No. 3,578,260 to Kell. In this prior art device, a pendulum is arranged to cause a subsidiary pawl to move from a first position in which it is out of engagement with a subsidiary ratchet wheel mounted on a reel to a second position in which it engages the subsidiary ratchet wheel, rotation of the reel in the direction resisted by the main pawl when the subsidiary pawl is in its second position being operative to move the subsidiary pawl from its second position to a third position. Movement of the subsidiary pawl from its second position to its third position is arranged to cause the main pawl to move from a first position in which it engages in one direction and a second position in which it does not engage.
Such prior art retractors lock up in a manner whereby tip to tip engagement of the lockbars with the ratchet wheels might take place which would result in "tooth skipping". Further, such prior art retractors are relatively noisy in operation. Thus, it is necessary that a retractor of such type have means for compensating for tolerances introduced into such retractors during manufacture and assembly so that they positively lock up without "tooth skipping" in a relatively quiet manner.